Incorporating blood-based liquid biopsy information into cancer staging: time for a TNMB system?

Tissue biopsy is the standard diagnostic procedure for cancer. Biopsy may also provide material for genotyping, which can assist in the diagnosis and selection of targeted therapies but may fall short in cases of inadequate sampling, particularly from highly heterogeneous tumors. Traditional tissue biopsy suffers greater limitations in its prognostic capability over the course of disease, most obviously as an invasive procedure with potential complications, but also with respect to probable tumor clonal evolution and metastasis over time from initial biopsy evaluation. Recent work highlights circulating tumor DNA (ctDNA) present in the blood as a supplemental, or perhaps an alternative, source of DNA to identify the clinically relevant cancer mutational landscape. Indeed, this noninvasive approach may facilitate repeated monitoring of disease progression and treatment response, serving as a means to guide targeted therapies based on detected actionable mutations in patients with advanced or metastatic solid tumors. Notably, ctDNA is heralding a revolution in the range of genomic profiling and molecular mechanisms to be utilized in the battle against cancer. This review will discuss the biology of ctDNA, current methods of detection and potential applications of this information in tumor diagnosis, treatment, and disease prognosis. Conventional classification of tumors to describe cancer stage follow the TNM notation system, heavily weighting local tumor extent (T), lymph node invasion (N), and detectable metastasis (M). With recent advancements in genomics and bioinformatics, it is conceivable that routine analysis of ctDNA from liquid biopsy (B) may make cancer diagnosis, treatment, and prognosis more accurate for individual patients. We put forward the futuristic concept of TNMB tumor classification, opening a new horizon for precision medicine with the hope of creating better outcomes for cancer patients.

Dermatofibroma-like granular cell tumor.

BACKGROUND: There have been several reports in the literature of dermatofibromas with granular cells. Here we report a granular cell tumor with the architecture of a dermatofibroma. This is the first report of this histological variant of granular cell tumor. The lesion was a 2.5-cm oval, hyperpigmented plaque present for "years" on the back of a 60-year-old African-American woman. METHODS: The specimen was processed using formalin fixation and paraffin embedding. Tissue sections were stained with hematoxylin and eosin. Immunohistochemical studies were performed with antibodies directed against S-100 protein, neuron-specific enolase, and factor XIIIa. RESULTS: Histopathologic examination revealed granular cells, some of which were spindle shaped, distributed singly and in small groups between collagen bundles resembling a dermatofibroma. Immunohistochemical studies showed the tumor cells to be positive for S-100 and neuron-specific enolase and negative for factor XIIIa. CONCLUSION: The immunohistochemical findings support the diagnosis of a granular cell tumor with a dermatofibroma-like pattern.

Primary localized extranodal hodgkin disease of the transverse colon.

Extranodal Hodgkin disease presenting as a primary localized neoplasm is uncommon, with rare case reports describing primary sites other than lymph nodes. The gastrointestinal tract is the most frequent site of involvement by extranodal Hodgkin disease, typically involving the stomach or small bowel. To date, we have been able to find only one fully documented case of Hodgkin disease of the sigmoid colon confirmed by immunohistochemical studies. We report a case of extranodal Hodgkin disease involving the transverse colon, presenting as inflammatory bowel disease and documented by light microscopic, immunohistochemical, cytogenetic, and molecular studies.

Immunohistologic evaluation of metastatic carcinomas of unknown origin: an algorithmic approach.

Pathologists are now asked frequently to determine the primary site for metastatic carcinomas of unknown origin (MCUO), using adjunctive morphological techniques such as electron microscopy, immunohistology, and other modalities. The authors present an algorithmic immunohistochemical approach to this problem that is based on their experience with over 2,800 routinely-processed epithelial malignancies of various types. These have been studied with antibodies to keratins, vimentin, epithelial membrane antigen, MOC-31, tumor associated-glycoprotein-72 (recognized by monoclonal antibody B72.3), prostate-specific antigen, thyroglobulin, gross cystic disease fluid protein-15, carcinoembryonic antigen, CA-125, CA19-9, placental alkaline phosphatase, S100 protein, and estrogen receptor protein. The algorithm that is structured around these 14 analytes is based on the relative predictive value of each marker, which in turn, determines its place in the sequence of interpretation. The authors' experience with this approach shows 67% accuracy with regard to the ultimately determined site of origin for MCUO, a figure which is similar to that reported by other investigators.

CD31 immunoreactivity in small round cell tumors.

CD31 has been shown to be a sensitive and specific marker for endothelial differentiation among epithelioid and spindled-pleomorphic human neoplasms. However, the role of this marker in the evaluation of small round cell tumors has not been evaluated. Formalin-fixed, paraffin-embedded tissue sections from 276 small round cell tumors, including 85 Ewing's sarcoma/primitive neuroectodermal tumors (ES/PNET), 52 rhabdomyosarcomas, 10 extraabdominal polyphenotypic small cell tumors, six desmoplastic small cell tumors, 11 neuroblastomas, 23 Wilms' tumors, 20 retinoblastomas, 13 esthesioneuroblastomas, and 56 small cell malignant lymphomas were stained with CD31 (JC/70A, 1:40), using a modified avidinbiotin-peroxidase complex technique, after citrate buffer microwave epitope retrieval. Among nonlymphoid small round cell tumors, four of 85 ES/PNET were at least focally reactive. No other lesion in this group was positive. In contrast, the majority of well-differentiated (11 of 17), intermediately differentiated (two of three), and lymphoblastic lymphomas (three of three) were positive. Small cleaved lymphomas (three of 13 follicular, one of 13 diffuse) were less often reactive, whereas small noncleaved lesions were negative. Although reactivity for CD31 in ES/PNET is uncommon, the presence of platelet/endothelial cell adhesion molecule in a small cell neoplasm should not in isolation be taken as evidence of hematopoietic origin. These results further define the utility of CD31 in the evaluation of human neoplasms.

MOC31 immunoreactivity in primary and metastatic carcinoma of the liver. Report of findings and review of other utilized markers.

Differentiating between primary tumors of the liver and metastatic lesions can, at times, be difficult. Various histochemical and immunohistochemical methods have been used in an effort to better delineate between hepatocellular carcinoma (HCC), especially the microglandular variant, primary cholangiocarcinoma, and metastatic adenocarcinoma; these ancillary studies can yield less than satisfactory results. Recently, anti-MOC31, a monoclonal antibody directed against a cell surface glycoprotein, has been shown to be helpful in distinguishing between adenocarcinoma and mesothelioma. This study addresses whether this antibody might be helpful in distinguishing between HCC, primary cholangiocarcinoma, and metastatic adenocarcinoma in the liver. Formalin-fixed, paraffin-embedded tissue sections from 15 HCC (including 10 microglandular variants), 14 primary cholangiocarcinomas, and 33 metastatic adenocarcinomas (7 colon, 1 lung, 8 breast, 4 GE jct/gastric, 9 pancreas, 2 small intestine, 1 renal, 1 ovary) were immunostained with anti-MOC 31 (1:40, Dako) after protease digestion and biotin block using a modified ABC technique. Positive staining was limited to membrane based reactivity; controls stained appropriately. Immunoreactivity for MOC31 was observed in 14 of 14 cholangiocarcinomas and 33 of 33 metastatic tumors. Staining was diffuse, intense, and readily interpretable, with rare exceptions. All 15 cases of HCC were negative. We conclude that cholangiocarcinoma and metastatic adenocarcinoma from a variety of sites express MOC31; HCC is uniformly negative for this marker. Anti-MOC31 may prove useful in the evaluation of liver neoplasms where primary hepatocellular and adenocarcinoma enter the differential diagnosis; it is not useful in separating primary cholangiocarcinoma from metastatic adenocarcinoma.

Angiosarcoma of the mandible: a case report and review of the literature.

Angiosarcoma is a rare malignancy that is characterized by endothelial cell differentiation. In the head and neck area, most of these lesions arise in the scalps of elderly individuals. Less commonly, angiosarcomas can be found within bone. The purpose of this report is to describe an example of angiosarcoma involving the floor of the mouth and right body of the mandible. The histopathologic and immunopathologic features of these lesions are also reviewed.

An immunohistochemical study of Na+/I- symporter in human thyroid tissues and salivary gland tissues.

The human Na+/I- symporter (hNIS) is the plasma membrane protein that mediates active iodide uptake into several tissues, such as the thyroid and salivary glands. To study the distribution and cellular localization of the hNIS protein, we have generated a polyclonal antibody that could detect the hNIS protein by immunohistochemical staining on tissue sections. In normal thyroids, hNIS expression is heterogeneous, and it is only detected in sporadic thyrocytes of a given follicle. The hNIS protein was not detected in thyroid carcinomas, yet it was detected in the majority of thyrocytes in Graves' thyroids. In salivary glands, hNIS protein was not detected in acinar cells, but it was detected in ductal cells. The hNIS proteins are clustered in the basal and lateral membranes in cells stained positive for hNIS.

Frequent mutation of p16 in squamous cell carcinoma of the head and neck.

RNA was isolated from 22 squamous cell carcinomas (SCCs) obtained from diverse sites within the head and neck and from matched normal tissue where available. Tissue samples were then screened for expression of RNA from tumor suppressor gene p16 by utilizing semiquantitative reverse transcriptase polymerase chain reaction (RT-PCR) analysis. p16-Specific PCR amplification products generated from tumor samples were subject to further analysis by direct DNA sequencing to determine if any tumor sample harbored a p16 mutation. The results show the presence of mutations in 10 of 22 (45%) of the tumor samples. Mutations comprise two identical point mutations, two small deletions (1 bp and 2 bp), one single-nucleotide insertion, four larger deletions, and an insertion/deletion. No mutations in p16 have been identified by analysis of PCR products generated from normal matched tissue, suggesting that p16 alterations are generated by somatic mutation and are not germline in origin. All 22 samples were analyzed additionally by immunohistochemistry for nuclear expression of the retinoblastoma (RB) tumor suppressor gene product. Results show lack of RB nuclear expression in only one sample, suggesting that mutation of RB is an infrequent event in the development of SCC of the head and neck (SCCHN).

Alterations in the expression of alpha6beta4 integrin and p21/WAF1/Cip1 in N-nitrosomethylbenzylamine-induced rat esophageal tumorigenesis.

Integrin alpha6beta4 is altered in many neoplastic cells, but no data exist to show this happens in esophageal neoplasms. To examine the expression of this integrin in rat esophageal tumorigenesis induced by N-nitrosomethylbenzylamine (NMBA), (alpha6 and beta4 expression was evaluated in normal esophageal epithelium, in NMBA-induced preneoplastic lesions, and in papillomas by quantitative reverse transcription (RT)-polymerase chain reaction (PCR) and immunohistochemical analysis. Because the 34 subunit of this integrin has been found to cause cell-cycle arrest by the induction of p21/WAF1/Cip1, the expression of p21/WAF1/Cip1 was also analyzed by RT-PCR. Compared with the levels in normal epithelium, the alpha6A, alpha6B, and beta4 integrin levels in esophageal papillomas were 1.9-, 2.2-, and 2.1-fold lower, respectively. RT-PCR analysis showed no significant differences in integrin levels between preneoplastic and normal samples, and northern blot analysis of the beta4 integrin produced results in agreement with the RT-PCR results. The p21/WAF1/Cip1 level was decreased 1.6-fold in preneoplastic tissues and 3.1-fold in papilloma samples when compared with the mRNA levels in normal epithelium. Immunostaining showed that alpha6beta4 integrin was localized at the basolateral surface of the basal cells in normal esophageal epithelium. In preneoplastic lesions, however, the expression of this integrin was not polarized and was expressed in basal cells as well as in suprabasal cells. Beta4 expression was significantly reduced and alpha6A expression was decreased and delocalized in papillomas. These findings suggest that alteration in alpha6beta4 integrin and p21/WAF1/Cip1 expression may be an important biomarker for tumor progression in NMBA-induced rat esophageal tumorigenesis.

Castleman disease mimicking a hepatic neoplasm.

Castleman disease, or angiofollicullar hyperplasia, is a rare cause of lymph node enlargement. This most commonly occurs within the thorax, although rare extrathoracic presentations have been described. Only two cases with hepatic localization have been reported. We present a case of Castleman disease within the porta hepatis masquerading as a hepatic neoplasm.

Genetic alterations in gastrinomas and nonfunctioning pancreatic neuroendocrine tumors: an analysis of p16/MTS1 tumor suppressor gene inactivation.

Neoplasms of the endocrine pancreas are extremely rare, and molecular mechanisms influencing their development are poorly understood. Nevertheless, gastrinomas have become a paradigm for the study of hormonally active tumors. In the present study, 12 gastrinoma and nonfunctioning pancreatic neuroendocrine tumor specimens were evaluated for genetic alterations of the p16/MTS1 tumor suppressor gene. DNA extracted from microdissected portions of paraffin-embedded tumor sections were examined for mutations and homozygous deletions using "Cold" single-strand conformation polymorphism and semiquantitative PCR-based analyses, respectively. Samples were also analyzed for the presence of 5' CpG island hypermethylation using methylation-specific PCR. The p16/MTS1 gene was found to be homozygously deleted in 41.7% of tumors and methylated in 58.3%, but no mutations were identified by single-strand conformation polymorphism analyses. Overall, 91.7% of the specimens demonstrated inactivating alterations in p16/MTS1. These data suggest that transcriptional silencing of p16/MTS1 is a frequent event in these rare and poorly understood tumors.

Maxillary malignant mesenchymoma and massive fibrous dysplasia.

This is the first report (to our knowledge) that describes a patient with massive polyostotic fibrous dysplasia involving the calvaria and facial skeleton that subsequently underwent transformation to a malignant mesenchymoma with elements of chondrosarcoma, osteosarcoma, and rhabdomyosarcoma arising in the maxilla. Malignant transformation occurred in the absence of prior radiation exposure, osteomyelitis, or known bony infarction. A review of the literature did not reveal any similar cases of massive fibrous dysplasia of the maxilla degenerating to multiple simultaneous malignant histotypes.

Endoscopic appearance of cryptosporidial duodenitis.

Cryptosporidial oocyst infection is a common cause of diarrhea in patients with AIDS. Concomitant symptoms can include crampy abdominal pain, nausea, vomiting, and anorexia. Esophagogastroduodenoscopy is then useful for delineating potentially treatable pathogens. We report a case of cryptosporidial duodenitis with characteristic endoscopic findings, biopsy correlate, and a review of the current literature. The endoscopic appearance illustrated strongly suggests proximal small bowel mucosal involvement with cryptosporidial oocysts.

Lymphangiomyomatosis recurrence in the allograft after single-lung transplantation.

The evolution of lung transplantation has offered an additional treatment option for patients with a variety of end-stage lung diseases, including some with systemic disorders. Lymphangiomyomatosis (LAM) is a multisystem disease of premenopausal women. The lung is the most frequently involved vital organ, and respiratory failure is the most common case of death. A small number of patients with LAM have undergone lung transplantation. This report describes a case of recurrent LAM in the allograft after single lung transplantation and discusses the implications of this finding.

CD31 immunoreactivity in mesenchymal neoplasms of the skin and subcutis: report of 145 cases and review of putative immunohistologic markers of endothelial differentiation.

CD31 has recently been reported as a specific marker of endothelial differentiation among non-hematopoietic human neoplasms. In order to address this contention in particular regard to tumors of the skin and subcutis, the authors undertook a comparative study that surveyed 145 mesenchymal lesions. The antibodies used were directed against CD31 (clone JC/70A) and CD34 (clone My10), and these were compared with binding of Ulex europaeus I agglutinin (UEA). Proliferations that were included in the category of vascular tumors included cavernous and capillary hemangiomas (17 cases); lymphangiomas (8); epithelioid ("histiocytoid") hemangiomas (3), papillary endovascular hemangioendothelioma (1), angiosarcoma (7), and Kaposi's sarcoma of the mixed angiomatoid and spindle-cell type (17). CD31-immunoreactivity was observed in 35 of 53 vascular lesions; the neoplastic cells in a single angiosarcoma and the spindle cells in each case of Kaposi's sarcoma (KS) were not labeled. In all of the latter tumors, however, staining for CD31 was identified in the endothelia of angiomatoid areas and non-neoplastic blood vessels. These results compared favorably with those seen with anti-CD34, which decorated 36 of 53 vascular tumors--including 8 of 17 KS cases--and UEA, which bound to the neoplastic cells of 36 lesions. In contrast, all of 92 non-endothelial tumors included in this study (34 nerve sheath tumors [30 benign; 4 malignant]; 39 fibrohistiocytic neoplasms [11 benign; 28 malignant]; 9 smooth muscle tumors [6 benign; 3 malignant]; 7 glomus tumors; and 3 giant cell fibroblastomas) were negative for CD31. UEA labeled 3 non-vascular neoplasms, whereas 38 lesions of that type were CD34-positive.(ABSTRACT TRUNCATED AT 250 WORDS)

Fibroma and giant cell tumor of tendon sheath: a comparative histological and immunohistological study.

Giant cell tumor of tendon sheath (GCTTS; "nodular tenosynovitis") and fibroma of tendon sheath (FTS) have traditionally been considered to be two points in a single neoplastic continuum. However, no systematic studies have addressed this concept directly to date. To more clearly define their relationship to one another, we studied five FTSs and seven typical GCTTSs by light microscopy and paraffin section immunohistochemistry. Tissue samples were stained for vimentin, desmin, smooth muscle actin (SMA), S100 protein, leukocyte common antigen (CD45), CD68 antigen (KP1), HAM56 antigen, alpha-1-antichymotrypsin (AACT), and MAC387 antigen. These reagents were chosen to address proposed "fibrohistiocytic" and myofibroblastic lineages for the two lesions. All tumors had a lobular appearance. GCTTS was more cellular than FTS; it contained conspicuous numbers of osteoclast-like cells, and the stroma was not extensively hyalinized. In contrast, FTS was matrix-rich, often with extensive stromal sclerosis, and contained only rare giant cells. Immunophenotyping of GCTTS showed that both the spindle cell and giant cell components were positive for vimentin, LCA, CD68, HAM56, AACT, and MAC387, suggesting monocyte-macrophage-like features. Limited reactivity for desmin and SMA also implied conjoint myofibroblastic differentiation. On the other hand, FTS showed focal staining with HAM56 (all cases) and for CD68 (one case); staining for vimentin and SMA was uniformly intense and diffuse. Based on these results, we conclude that GCTTS and FTS both exhibit varying degrees of monocyte-macrophage-like and myofibroblastic differentiation. The predominance of macrophage-related determinants in GCTTS and myofibroblastic markers in FTS supports the premise that these lesions represent phenotypic extremes of a single clinicopathologic entity.